"We have had some fantastic partnerships at this club over the years," said Ferguson.
"The first season with Andy Cole and Dwight Yorke was incredible but most of them do take time.
"Both have great attributes. They have speed and courage and they are able to beat a man, so all the things are there.
"Maturity is what we want to see now, and also authority and timing. "Once that comes hopefully they will be at our club showing everyone what great players they are.
"The evidence is good at the moment. I am encouraged by that. They are young players and hopefully that development gets better. The signs are very good at the moment, that is all I can say. I am delighted with that because they are so young."